The liquid crystal display has many advantages such as thin body, power saving, no radiation and so on, and has been widely used. Most of the liquid crystal displays on the market are liquid crystal displays of backlight type, which include a liquid crystal panel and a backlight module. The working principle of the liquid crystal panel is to place liquid crystal molecules in two parallel glass substrates, and apply a driving voltage on the two glass substrates to control the rotation direction of the liquid crystal molecules, so as to refract the light of the backlight module to produce a picture.
Among them, thin film transistor liquid crystal display (Thin Film Transistor-Liquid Crystal Display, TFT-LCD) has gradually occupied a dominant position in the display field due to its low power consumption, excellent picture quality and high production yield. Likewise, the thin film transistor liquid crystal display includes a liquid crystal panel and a backlight module. The liquid crystal panel includes a color filter substrate (also referred to as a CF Substrate) and a thin film transistor array substrate (Thin Film Transistor Substrate, TFT Substrate). A transparent electrode is present on the opposite inner side of the substrate. A layer of liquid crystal molecules (Liquid Crystal, LC) is sandwiched between the two substrates. The liquid crystal panel realizes the display purpose by controlling the orientation of the liquid crystal molecules through an electric field, changing the polarization state of the light, realizing the penetration and blocking of the optical path though the polarizing plate.
At present, the manufacturing procedure of LCD open cell (Liquid Crystal Display open cell) is generally divided into pre-procedure, mid-procedure and post-procedure. The pre-procedure is mainly to manufacture a TFT (Thin Film Transistor) glass. The mid-procedure mainly refers to attaching the TFT glass and the color filter, and adding the upper and lower polarizing plates; and the post-procedure refers to pressing a driver IC (integrated circuit) and a printed circuit board to the TFT glass, and an open cell (liquid crystal panel) is completed. In the post-procedure, a high temperature and high humidity test is required to ensure the resistance of the open cell after bonding is complete in the production line.
For example, when the liquid crystal panel is subjected to high temperature and high humidity test, a plurality of external test circuit boards are required to provide a picture and a clock signal. The external test circuit board has a poor resistance to high temperature and high humidity, and the external test circuit board is easily damaged in the repeated high temperature and high humidity tests.
In addition, the conventional picture display function test is to judge the picture displayed on the display panel by a human eye. This detection method is simple, but the biggest problem is that manual detection is required, and manual comparisons of the test results are required, which is inefficient and easy to make mistakes.